A description of communication networks and systems can be found in particular in Technical Specifications published by standardisation bodies such as for example 3GPP (3rd Generation Partnership Project), . . . etc. The example of IMS (IP Multimedia Subsystem) as specified by 3GPP will be considered more particularly in the following, as an example to which the present invention applies. However the present invention is not limited to such example.
IMS architecture supports value-added services thanks to entities such as in particular Application Servers (ASs). To support such services, Application Servers interact with other entities such as in particular a subscriber database, also called Home Subscriber Server (HSS), holding subscriber data.
The interface between AS and HSS is called Sh interface, it is specified in particular in 3GPP TS 29.328 and 3GPP TS 29.329.
Data accessible via Sh interface include non-transparent data and transparent data. Non-transparent data are data that are understood both syntactically and semantically by the HSS. Transparent data are data that are not understood by the HSS. It is data that an AS may store in the HSS to support its service logic. One example is data (called Repository Data) that an AS stores in the HSS, using it as a repository. Such data repository may be shared by more than one AS implementing the same service.
Within 3GPP IMS framework, the HSS is being positioned as a centralised user profile repository that stores standard IMS-HSS user data (non-transparent data) as well as AS-related user data (transparent data, or Repository Data).